This invention relates generally to fluid pumps and in particular centrifugal and screw type fluid pumps.
Many of the screw type fluid pumps of the prior art were tilted at an angle to the level of fluid being pumped so that the fluid would be captured between the helical screw blades and the cylindrical wall of the pumping container. As the pump drive rotated the screw, the water would be trapped and move up the cylinder to be discharged out of the top of the tube.
Other screw type pumps used both a rotating helical screw and a contra-rotating cylinder equipped with outward directed feed vanes at the collector end of the rotating screw. The feed vanes were used to deliver the highly viscous feed material into the intake end of the screw to force the material onto the feed screw.
All the prior art screw type pumps operated at generally low rotational speeds. As the size of these pumps increased, so did their weight. This required larger bearings and increased bearing loads and friction loses. As a result, larger pump motors were required.
Prior art pumps relying on centrifugal force usually operated at very high rotational speeds causing the pumped fluid to cavitate and erode the pump impeller.
The pumping apparatus of the present invention is an improvement over the prior art pumps. It uses the pumping fluid itself to carry the weight of the pump to minimize frictional losses and to eliminate the need for high weight carrying bearings Its rotating symmetrical pump mass allows it to operate at low rotational speed and yet generate sufficient centrifugal force and high torque to elevate large volumes of water to a high level continuously. As a result, only a small horsepower motor is required.